FYI, I've noticed an issue when switching from Fullscreen/Fill Screen/Windowed mode in Windows - it seems nothing from the layout is redrawn, although if you press ESC you can see the exit message - even that appears to be at the wrong resolution to not fit on the screen.

I can confirm that I'm having the same (or similar) problem with OSX. After change from FILL to WINDOW and in oposite direction - I'm getting blank (black) screen. If I switch back and forth to another theme, everything is ok.